相变存储器材料设计与多尺度模拟的研究进展

沈雪阳, 褚瑞轩, 蒋宜辉, 张伟

Progress on Materials Design and Multiscale Simulations for Phase-Change Memory

SHEN Xueyang, CHU Ruixuan, JIANG Yihui, ZHANG Wei

图6 面向Sb₂Te₁相变合金光波导器件应用的多尺度模拟^[111]

Fig.6 Multiscale simulation of Sb₂Te₁ phase change alloy for waveguide devices ^[111]
(a) local structural snapshots of amorphous and crystalline Sb₂Te₁ (amor.—amorphous; crys.—crystalline; Sb and Te atoms are rendered as yellow and green spheres, respectively)
(b) changes in dielectric function upon crystallization and Te ordering (ε₂—imaginary part of the dielectric function, I_Te—concentration of Te atoms in Te-rich layers)
(c) schematic of a Sb₂Te₁ waveguide device (ITO—indium tin oxide,

h_{I T O}

—height of ITO,

h_{S b_{2} T e_{1}}

—height of Sb₂Te₁ layer,

d_{S b_{2} T e_{1}}

—length of Sb₂Te₁ layer, w_wg—width of the waveguide, h_wg—height of the waveguide, T—transmittance, P₁—power of incident light, P₂—power of transmitted light)
(d) transmittance profiles of different phases
(e) corresponding electric field |E| of the x-z plane of Sb₂Te₁ device in different phases, the color bar below shows the normalized electric field intensity (PCM—phase-change materials)